S3) Lymphatic Drainage of the Head and Neck Flashcards
What does the lymphatic system consist of?
- Lymph nodes
- Lymphatics
- Lymph fluid
What is the purpose of the lympathic system?
Continuous removal of residual tissue fluid from the extracellular space (via a series of lymph nodes) to be returned back to blood circulation
Lymph is just tissue fluid which has entered the lymphatic capillary.
Identify some of the contents of lymph
- Lipids (chylomicrons from gut lymphatics)
- Small proteins
- Damaged cells
- Tissue fluid
- Bacteria
How much lymph does the body produce a day?
3 ‐ 4 L of lymphatic fluid produced per day
What danger is associated with the lymphatic vessels?
A route for the spread of infection and malignant disease
Illustrate how uni-directional flow occurs in the lymphatic system
Tissue fluid → lympathic capillary → lymphatic vessels → lymphatic nodes → lymphatic vessels → lymphatic trunks → lymphatic ducts → venous system
The lymphatic system is a low pressure system with no central pump.
How does the lymph flow?
- Valves: passive and intrinsic constriction
- Pulsation of an artery (close association)
- Muscle contraction
Where in the venous circulation does the lymph drain?
Lymphatic system ends in two main lymphatic ducts which drain into subclavian veins
What is lymphoedema?
Lymphoedema is the abnormal collection of protein‐rich fluid causing tissue swelling due to compromised lymphatic system
Lymphoedema is a chronic condition.
Identify 5 of its causes
- Removal / enlargement of lymph nodes
- Infections e.g. certain parasites
- Damage to lymphatic system e.g. cancer treatments
- Lack of limb movement
- Congenital
Provide 3 examples of lymphoid organs in the body
- Spleen
- Tonsils (Waldeyer’s ring)
- Thymus
Describe the structure of lymph nodes
Connective tissue structures:
- Tough fibrous outer capsule
- Reticular connective tissue inside
Describe, briefly, how lymph nodes provide defence against infection
- Physical filter
- Phagocytic filter
- Lymphocytes: activate and proliferate in response to antigens
Enlarged lymph nodes is a very common patient presentation.
Which two underlying conditions cause this?
Lymphadenopathy:
- Infection – most common, tender, mobile
- Cancer – hard, matted, non-tender
What should one do when a patient presents with enlarged lymph nodes?
- Comprehensive history
- Examine the area of tissue it drains
- Examine other lymph nodes and body systems (if malignancy is suspected)
Lymph nodes in the head and neck can be classified into two groups.
Identify them and describe their function
- Regional: receive drainage from scalp, face and neck (ring)
- Terminal: receive drainage from regional nodes (vertical)
Describe the relative depth of terminal and regional lymph nodes
- Regional = superficial
- Terminal = deep
Identify the 5 regions in body where collections of lymph nodes may be palpable
How many lymph nodes are in the body?
Of those, how many can be found in the neck?
- 800 lymph nodes in the body
- 300 lymph nodes in the neck
Where are regional lymph nodes located?
Superficial to the investing layer of deep cervical fascia
Where are the terminal lymph nodes located?
- Deep to the investing layer of deep cervical fascia
- Most are associated with IJV (in carotid sheath)
Identify the following superficial lymph nodes 1-5:
1) Submental
2) Submandibular
3) Pre-auricular
4) Post-auricular
5) Occipital
Identify the following cervical lymph nodes 6-8:
6) Superficial: EJV
7) Posterior: EJV
8) Anterior: AJV
Identify the following deep lymph nodes 9-11:
9) Jugulo‐digastric (tonsillar node)
10) Jugulo‐omohyoid
11) Supraclavicular lymph nodes
What do supraclavicular lymph nodes do?
Supraclavicular lymph nodes oversee transport of lymph from thoracic cavity and abdomen
Where are supraclavicular lymph nodes located?
Supraclavicular nodes are found in the root of the neck on either side
What is Virchow’s node?
Virchow’s node is a lymph node in the left supraclavicular fossa
What is Trosier’s sign?
Trosier’s sign is the enlargement of the left supraclavicular node (Virchow’s node) secondary to metastatic abdominal malignancy
Where is the jugulo-digastric node located and what does it do?
The jugulo-digastric node is located just below and behind the angle of the mandible and is concerned with lymph drainage of the palatine tonsil, oral cavity and the tongue
What does the jugolo-omohyoid lymph node do?
The jugulo-omohyoid node is mainly associated with the lymph drainage of the tongue, oral cavity, trachea, oesophagus and the thyroid gland
Where do deep lymph nodes drain?
Deep cervical lymph nodes eventually drain via the thoracic duct (or right lymphatic duct) into the subclavian vein
The deep lymphatic vessels converge to form left and right jugular lymphatic trunks.
Describe their location
- Left jugular lymphatic trunk: joins thoracic duct at root of neck
- Right jugular lymphatic trunk: empties into right lymphatic duct at root of neck
Why do some diseases involve both regional and terminal cervical lymph nodes?
Many structures of the head and neck drain via superficial lymph nodes into the deep cervical lymph nodes
What is Waldeyer’s ring?
Waldeyer’s ring is an annular collection of lymphatic tissue (nodules) surrounding the entrance to the aerodigestive tracts
Identify the tonsils which form Waldeyer’s ring
- Lingual tonsil
- Palatine tonsils
- Tubal tonsils
- Pharyngeal tonsils
Which tonsils are affected by tonsillitis?
Palatine tonsils
Which of the lymphoid tissue in Waldeyer’s ring can one most readily view when examining a patient?
Palatine tonsils
Which tonsils of Waldeyer’s ring are also called the adenoids?
Where are they located?
Pharyngeal tonsils – located in the roof of the nasopharynx (behind the uvula)
Why might an enlargement of the adenoids cause middle ear problems?
- An enlarged adenoid can block the Eustachian tube
- Mucus cannot drain properly and accumulates
- Infection easily spreads into middle ear
